Hartshorne: God's omnipotence should be about total influence and the effects against resistance
through our free will we can resist against God
this doesn't mean that he is not omnipotent as He can still overcome this resistance
when cutting a rose branch, the branch resists the clippers, but ultimately, the resistance is stronger, leading to the branch being cut
if the clippers were omnipotent then the rose would not resist - clipping would be easy
it is not impressive to conquer things that put up no resistance - it is better to be overcome the resistance